Kiely & Lin in U.S. Pat. No. 4,833,230 described a general method for preparing polyhydroxypolyamides from aldaric acids, and in particular poly(alkyleneglucaramides), as for example, poly(hexamethyleneglucaramide), from glucaric acid obtained from the oxidation (typically nitric acid oxidation) of glucose. Such polymers based on glucose are of particular interest because of the ready availability and low cost of glucose. The patent describes a process in which the calcium salt of glucaric acid is converted with the acid form of a cation exchange resin to a mixture of forms of glucaric acid in aqueous solution. [Hirasaka et al, Chem. Pharm. Bull., 13, (1965) reported that glucaric acid in aqueous solution can exist as the diacid, acid/lactone and dilactone.] Water is removed from the mixture, which without separation is then esterified with acid catalyst and an alkanol. The esterified glucaric acids, hereinafter described as "activated glucarates", without separation are then polymerized with primary diamines to yield poly(alkyleneglucaramides). In summary, the Kiely & Lin patent describes a two step conversion of a salt of glucaric acid to activated glucarates. The first step converts glucaric acid salt to a mixture of glucaric acid forms using the acid form of an ion-exchange resin and water as solvent. The water is then removed by a distillation (evaporation) process. The second step involves conversion of the mixture of glucaric acid forms to a mixture of activated glucarates with acid in alkanol. The activated glucarates then are used as monomers for polymerization with appropriate aliphatic diamines in the presence of a tertiary amine to form poly(alkyleneglucaramides).
Smith, J. Chem. Soc., 632 (1944), had previously prepared these glucaric acid lactones by neutralization of potassium acid glucarate with aqueous sulfuric acid and similarly removing the water before esterification.
More recently Hashimoto et al., Makromol. Chem., Rapid Commun., 11, 393 (1990), have described the preparation of a poly(aralkyleneglucaramide), poly(p-xylyleneglucaramide), a type of polyhydroxypolyamide based upon the aralkylenediamine p-xylylenediamine as the diamine monomer using a specific activated glucarate (a dilactone), D-glucaro-1,4:6,3-dilactone, which had been prepared in a similar fashion from an aqueous solution of potassium acid glucarate as the glucarate monomer.